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Mini Event Emitter

Easy · Events

Node's EventEmitter lets code subscribe to named events. Build a tiny version, MiniEmitter, with two methods:

- on(event, listener) registers a listener for event

- emit(event, payload) calls that event's listeners in the order they were added, passing payload. Like Node, it returns true if the event had listeners, otherwise false.

(Node's emit can pass any number of arguments; here there is just one payload.)

The driver runEmitter(ops) is already written. Listeners are identified by ids; each writes "<id>:<payload>" to a log, and every emit writes "<event> -> <result>" after its listeners ran. The log is returned.

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